Commutator-brush



W. C. HOOD.

COMMUTATOR BRUSH.

APPLICATION FILED OCT. 28. 19KB.

1 352,408, Patented Sept. 7, 1920.

UNITED STATES WILLIAM PATENT OFFICE.

O. HOOD, OF CHICAGO, ILLINOIS.

COMMUTATOR-BRUSH.

Specification of Letters Patent.

Patented Sept. *7, 1920.

Brushes, of which the followingis a specification.

This invention relates to improvements in commutator brushes and has among its salient objects to provide a construction in which the brush has a wiping action across the face of the commutator to keep the same clean and thus reduce commutator sparking to a minimum; to provide a construction in which the contacting edges of the face of the brushes are so notched to provide air cooling passages which reduces the heat of the commutator; to provide a construction of the above character in which the notches on the contacting faces of the brush members are so arranged as to provide a maximum contacting surface or in other words, to provide a continuous contact with the commutator, substantially across the entire face of the brush; to provide a construction which, while having the cleaning action referredto, obviates any tendency to form ridges or grooves on the commutator; to provide a construction which can be economically manufactured and is at the same time reliable in operation, and in general to provide an improved construction of the character referred to.

In the drawings: I

Figure l is a plan View of the commutator and two pair of brush members. V

Figs. 2 and 8 are detail views of the brush members showing right and left hand arrangement of the notched portions.

Fig. 4 is an end view.

Referring'to thedrawings, 1 designates the commutator which in the present instance is provided with two pair of my improved brush members 2 and 3 arranged at the opposite sides of the commutator. These brush members 2 and 3 are preferably made of hard or softcarbon. The brush members 2 are provided on their face with a plurality )f diagonally extending notches 4. These 7 notches, one end notches 4 are spaced apart as shown clearly in the drawings and the outside notches at either edge of the brush face, extend to or closely approach the side edges thereof. The other brush members 3 .of eachpair is provided with similar dia onally extending spaced apart notches 5 w ich notches, how-, ever, run in the opposite direction to those in brush members 2. These notched faces of the brushes by the wiping action referred to, serve to keep the face of the commutator clean but because of their diagonal positions, do not tend to form ridges or grooves, in the face of the commutator. The arrangement further insures of a continuous contacting surface across the face of the commutator with. the minimum amount of friction. It is to be noted that inasmuch as the notches are opened at-the ends, they permit a current of air to be constantly sweeping around the commutator and tending to cool the latter and also tending to permit any dirt or detritus collected from the face of the commutator to pass out through the notches.

In the drawings, I have shown two pair of brushes at each side of the commutator. It is to be understood that a single pair of brushes can be used, one at each side of the commutator or the number of brushes may be multiplied to meet the required -conditions. In some cases as many as a hundred brushes or more may be used on a single commutator.

The invention is not limited to the details of constructions as shown except as follows in the appended claims.

claim as my invention:

1. A pair of commutator brushes each having on its contacting face a series of diagonally extending spaced apart open-ended notches, the series of notches on one brush extending in a reverse direction to the series of notches on the other brush.

2. A commutator brush having on its contacting surface a plurality of diagonally extending spaced apart parallel open-ended of one notch lying in substantially the same transverse plane as the opposite end of the adjacent notch.

f WILLIAM G. HOOD. 

